Machine and process for production of three-dimensional stirrups

ABSTRACT

Machines and processes for production of three-dimensional stirrups ( 1   a ) with two converging legs ( 4,5 ), from rods, wire or other material of any cross-section. A planar stirrup ( 9 ) with parallel legs is either produced with the aid of a bending head ( 19 ) by making two bending operations, or is furnished in prepared, precut form and is restrained, for example by a grip or jaw ( 26 ). Afterwards, utilizing a stirrup-leg adjustment mechanism ( 25 ) located immediately following this bending head ( 19 ), which mechanism ( 25 ) includes an arm ( 16 ) that may move in reciprocation with the aid of a suitable mechanism ( 18 ) and has a hook ( 17 ) at its end, the free leg ( 5 ) of the planar stirrup ( 9 ) is trapped by the hook ( 17 ). This trapped free leg ( 5 ) is moved towards the opposite leg ( 4 ) as arm ( 16 ) reciprocates, covering an appropriate distance. Finally, the third dimension is generated by bending simultaneously at locations ( 12, 13 ) with a suitable bending mechanism ( 22 ) that is located after the stirrup-leg adjustment mechanism ( 25 ).

This application claims foreign priority under 35 U.S.C. 119 to priorGreek (GR) National Application No. 20060100262 filed on May 4, 2006,the entire contents of which are hereby incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention refers to a machine and process for production ofthree-dimensional stirrups 1 a from rods, wire, or other material of anycross-section. Such three-dimensional stirrups may, for example, beemployed for joining construction elements of reinforced concrete thatare either fabricated on-site at construction sites, or areprefabricated.

2. Description of Related Art

With reference to FIGS. 9-10 labeled as prior art, three-dimensionalstirrups 1 a of the type depicted in FIGS. 9-10 were typically producedaccording to the following techniques:

(a) Manual formation with the aid of hand-operated or semiautomatictools. In this regard, it may be understood that U.S. Pat. No. 919,206to Newlin discloses a manually-operated rod bending tool applicable inbending rods employed for reinforcing concrete. U.S. Pat. No. 1,425,261to Kardong also discloses a manually-operated rod bending toolapplicable in bending rods used for reinforcing concrete. A more recentpublication, U.S. Pat. No. 6,997,030 to Williams, also discloses amanually-operated rod bending tool applicable in bending rods used forreinforcing concrete. U.S. Pat. No. 3,908,425 to Ware discloses amanually-operated power tool suitable for bending rods used forreinforcing concrete.

(b) With the aid of automated stirrup machines having a first bendingmechanism, bending on only one plane, where is first produced a planarstirrup 3 a with converging side legs 4,5. This first bending mechanismthus makes at least four bendings. Afterwards the planar stirrup 3 a ismanually positioned on another suitable mechanism, usually hand-operatedor semiautomatic, where for the generation of the third dimension, bendsare made of the two angles out-of-the plane at locations 12,13simultaneously.

(c) With the help of automatic stirrup machines, which include anarrangement of two bending mechanisms, wherein a first bending mechanismgenerates the planar stirrup 3 a, with converging legs 4,5. This firstphase requires at least four bendings. Then the second bendingmechanism, which includes an arrangement of two parallel arms, one fixedand a second which moves cyclically about the fixed one, bends twoangles simultaneously at locations 12,13 so that the third dimension ofthe stirrup product is formed.

These existing machines, processes, and techniques present numerousproblems which it would be desirable to alleviate. Again havingreference to FIGS. 9-10 labeled prior art, first, it may be noted thatsuch three-dimensional stirrups 1 a are typically placed in metalliccases with shape U or double-U, which are then covered with a suitablyshaped cover of metal, synthetic materials, cardboard, or other suitablematerial. In this regard, it is required that their legs 4,5 which arelocated on one plane converge at suitable angle, that their opposingsides 6, 7 that are located on the other plane be mutually parallel.Thus, in order that the three-dimensional stirrups 1 a be produced withthese characteristics, it is necessary that at least five bendings mustoccur. First, stirrups taking a planar shape 3 a are formed by effectingfour bendings on one plane. Subsequently there are formed the two anglesthat establish the third dimension. These usually are bentsimultaneously in the fifth bending with a suitable mechanism.

The first technique (a) discussed above has a high cost of productionsince it requires the manual involvement of laborers, it istime-consuming, and productivity is low. Furthermore, the quality of theresulting three-dimensional stirrups 1 a is not always that required fortheir further use. Since the shape of the in-question product does nothave absolute precision as to its geometric characteristics this createsdifficulties in its placement in the metallic cases.

In the second technique (b) discussed above, there again must occur atleast five bendings of the material.

In the third technique (c) discussed above, there again must also occurat least five bends of the material. Here the disadvantage is that thebends in the third dimension must fall precisely on the two opposinglocations 12,13 of the planar shape 3 a, something which is not feasiblewith precision, because of the torsions that the material has and thequalitative alterations that are present within the same spool fromwhich it originates. The result is that the thus-produced productcreates difficulty in its further application.

It may be noted from the aforegoing discussion that all of thetechniques according to the state of the art have a commoncharacteristic that the converging legs 4,5 are produced first in theplanar stirrup 3 a by effecting at least four bending operations. Thethird dimension of the shaped stirrup is generated subsequently.

SUMMARY OF THE INVENTION

It is an object of this invention to present versions of innovativemachines and processes concerning the automated production ofthree-dimensional stirrups 1 a, 1 b, 1 c, 1 d, 1 e from rods, wires, orother suitable materials of any cross-section, wherein first a planarstirrup 9 with parallel legs 4,5 is produced by making two bends. Thenthe free leg 5 is moved towards the opposite leg 4 which is restrainedfrom moving. Finally, a third product dimension is created by bendingthe stirrup out of the plane simultaneously at suitable locations 12,13.In this fashion the creation of the planar stirrup 9, which leads to thefinal three-dimensional stirrup 1 a, may require only two bendingoperations.

In relation to the enumerated problems with the previous existingtechniques discussed in the aforegoing description, and in contrastthereto, we note several exemplary specific advantages that may beafforded by versions of the invention:

-   -   The time for production of the stirrups is shortened.    -   The cost of production is reduced.    -   As a result of the high quality of the product and the greater        precision of its shape, the further placement of stirrups in the        special cases is easy and in parallel time is economized here        also.    -   As a result of the requirement of two less bendings for the        generation, we have a fair amount of economization of energy        during the production of each three-dimensional stirrup 1 a.        This may be considered as something significant if we        contemplate that these products are produced at many thousands.

More details about the machines and processes according to the presentinvention will be better comprehended in the immediately followingdetailed description of exemplary particular implementations of versionsof the invention. The machines and processes are described in theattached figures, in the sense of non-restrictive examples and withoutlimitation in the range of the applications of the machines andprocesses. These and other features, aspects, and advantages of thepresent invention will become better understood with regard to thefollowing description, appended claims, and accompanying drawings,where:

BRIEF DESCRIPTION OF THE DRAWINGS

The machines and processes according to the present invention will bebetter understood with reference to the exemplary attached drawingfigures, where:

FIG. 1 depicts a first form of three-dimensional stirrups that may beproduced in accordance with the present invention.

FIG. 2 depicts a second form of three-dimensional stirrups that may beproduced in accordance with the present invention.

FIG. 3 depicts a third form of three-dimensional stirrups that may beproduced in accordance with the present invention.

FIG. 4 depicts a fourth form of three-dimensional stirrups that may beproduced in accordance with the present invention.

FIG. 5 depicts a fifth form of three-dimensional stirrups that may beproduced in accordance with the present invention.

FIG. 6 helps depict in idealization the process of production and itskinematic requirements, according to the present invention and shows aplanar stirrup.

FIGS. 7-8 likewise help depict in idealization a process of productionand its kinematic requirements, according to the present invention.

FIGS. 9-10 depict idealized a process of production of thethree-dimensional stirrups according to the prior art.

FIG. 11 schematically depicts a version of the machines able to effectthe processes of production of three-dimensional stirrups according tothe present invention.

FIG. 12 schematically depicts another version of the machines able toeffect the processes of production of three-dimensional stirrupsaccording to the present invention.

DETAILED DESCRIPTION

Definitions: For simplicity and ease of reference thereto, the terms“wire,” “wire rods,” “rods,” “rod material,” and “material of anycross-section,” are used interchangeably and equivalently throughout theremainder of the detailed description and appended claims. Thus,artisans in the art will readily understand that the term “wire” withinthe appended claims encompasses and includes the aforesaid “rods,” “wirerods,” “rod material,” and generally “material of any cross-section”without differentiation unless such differentiation is explicitly setforth. Thus, all these known, utilizable materials of prismaticcross-section may be conveniently and clearly referred to innon-limiting brief form by the terms “wire,” or “rod” within the text ofthe description which immediately follows and within the appendedclaims.

With reference to FIGS. 1-8 and 11, the processes concern the automatedproduction of three-dimensional stirrups 1 a, 1 b, 1 c, 1 d, 1 e fromrods, wire or other suitable materials of any cross-section. There isproduced first a planar stirrup 9 with parallel legs 4,5 by making twobends, or alternatively there may be received a prepared and precutplanar stirrup 9. Afterwards the free leg 5 is biased at a suitablelocation 11 towards the opposite leg 4, which is held unmoved. Finally,simultaneously bending at suitable locations 12,13 bends the stirrup outof the plane, so as to create a third dimension. In this fashion onlytwo bending operations may be needed for the creation of the planarstirrup 9 leading to the final three-dimensional stirrup 1 a.

This process effects the production of three-dimensional stirrups 1 afrom rod, wire, or other suitable material of any cross-section. Suchthree-dimensional stirrups 1 a typically have the two legs 4,5 on whichare found the two ends of the stirrup 1 a, being on the same plane andconverging at a particular angle, though some of the other sides, thatare located on a different plane, may converge under a different angleor may be parallel. In the present process preferably there is producedfirst the planar stirrup 9 from suitable layout; afterwards, with asuitable mechanism the leg 5 having a free end is trapped at a suitablelocation 11 and is pulled towards the opposite leg 4, so that the twolegs' 4,5 two sides converge under a suitable desired angle. Finally,with another suitable bending mechanism 22 there are createdsimultaneously at least two sides 6, 7 under a suitable angle, outsideof the plane, so that there is formed the third dimension of theproduct. A cutting may follow. The result is that the two free legs 4,5converge under the desired angle even though the opposite sides 6, 7 inthe other plane maintain their geometry as it was prior to the creationof the third dimension. In another version of the method as describedabove within the present paragraph, there may be produced simultaneouslymore than one three-dimensional stirrup 1 a, applying the process tocorresponding plural locations.

In a version of the process according to the immediately aforegoingparagraph, as further understandable with regard to FIG. 12, thetwo-dimensional stirrups 9 may first be prepared and shaped in thesuitable dimensions and then be supplied to suitable mechanisms 25, 22so as to undergo the further processing for the shaping of theend-product product 1 a, 1 b, 1 c, 1 d, 1 e.

In a further version, in the processes according to the immediatelypreceding two paragraphs there may be received from the suitable layoutmore than one (i.e. plural) two-dimensional stirrups 9 simultaneously inplural corresponding locations of receipt by suitable mechanisms so thatthey undergo further processing for the shaping of the final product.

It must be explained also, with particular reference to FIGS. 2-5, thatwith the present process it is possible to produce three-dimensionalstirrups, which in the third dimension can have any form, such as forexample non-perpendicular angles, uneven leg sides with oblique slantedaxial bend 1 b, with curved configuration 1 c, with triangularconfiguration 1 d, with polygonal configuration 1 e and others.

In one aspect, and with reference to FIG. 11 of the appended drawings,the process may be implemented by an intermediate stirrup-leg adjustmentmechanism 25 which is preferably disposed in stirrup machines having thefollowing characteristics: they have an arrangement of an advancementmechanism 21 for the rod, wire or other suitable material, that may comefrom a spool or from straightened pieces; they have a bending head 19that bends the material in one place, creating planar stirrups; theyhave a cutter 20 for cutting the material after the creation of thethree-dimensional stirrup 1 a by a second bending mechanism 22. Thissecond bending mechanism comprises a stationary arm 23 and a second arm24 that can move cyclically around the stationary arm 23 thereby bendingthe two legs 4,5 of the planar stirrup simultaneously. In such anarrangement, the stirrup-leg adjustment mechanism 25 is placed betweenthe first bending mechanism 19 and the second bending mechanism 22 andcomprises one arm 16 that can move in an alternating, reciprocatingmanner with the aid of a suitable mechanism 18 and at a suitable angleas to the legs 4,5 of the planar stirrup 9 trapping with the aid of asuitable hook 17 the free leg 5 which it moves towards leg 4. Traversinga suitable distance, it holds the leg 5 until the second bending head 22bends the two legs 4,5 at suitable locations 12,13 creating the thirddimension. Afterwards the cutting of the material of leg 4 at a suitablecutting location is made by cutter 20.

The machines of the present invention are further described withreference to FIGS. 11-12 and FIGS. 1-8 of the appended drawings.

An intermediate stirrup-leg adjustment mechanism 25 for the productionof three-dimensional stirrups 1 a, 1 b, 1 c, 1 d, 1 e, with convergingfree legs 4,5, from rod, wire, or other suitable material of anycross-section, is placed in stirrup machines. Such stirrup machines mayinclude an arrangement of an advancement mechanism 21 for the rod, wireor other suitable material that may be supplied from a spool or fromstraightened pieces. In this case they may include a first bendingmechanism 19 that bends the material in one plane to generate planarstirrups 9. Also in this case they may also include a cutter 20 for thecutting of the material after the generation of the three-dimensionalstirrup 1 a, 1 b, 1 c, 1 d, 1 e by a second bending mechanism 22. Thissecond bending mechanism 22 comprises a fixed arm 23 and a second arm 24that can move cyclically around the fixed arm 23 bending thus the twolegs 4,5 of the planar stirrup simultaneously.

Alternatively, such stirrup machines may receive prepared and precutplanar stirrups 9 trapping one free leg 4 with the aid of a grip or jaw26. This is schematically depicted in FIG. 12. In this case, thearrangement includes the grip or jaw 26 that can receive the planarstirrup restraining it via leg 4. Thus, stirrup-leg adjustment mechanism25 may be used also in stirrup machines that work planar prepared orpreformed, precut planar stirrups 9, and that have an arrangementincluding only the second bending head 22 which creates the thirddimension. It will be readily understood from the aforegoing descriptionthat in this second case the first bending mechanism 19 is not necessaryand may be absent.

Assuming the first case, above, for illustration, the intermediatestirrup-leg adjustment mechanism 25 is placed between the first bender19 and the second bender 22, under the plane of the under-productionproduct. It comprises an arm 16 that can move with the aid of suitablemechanism 18 that produces a controlled, alternating, reciprocatingmotion. This may, for example, be a motor or drive mechanism 18. The arm16 moves at a suitable selected angle relative to legs 4,5 of the planarstirrup 9, trapping with the aid of a suitable hook 17 the free leg 5,11, and adjusting it towards the other leg 4. The arm 16 traverses asuitable distance, holding it until the second bending head 22 bends thetwo legs 4,5 at the suitable locations 12,13 creating the thirddimension.

As a further alternative, the stirrup-leg adjustment mechanism 25 may beplaced above the plane of the subjected-to-generation product. Thus itwill be readily understood that the stirrup-leg adjustment mechanism 25may be located either under the plane of the under-production part orabove it.

As a further alternative, the stirrup-leg adjustment mechanism 25,according to the aforegoing description may trap the free leg 5 of theplanar stirrup 9 with the aid of grip. Thus it will be understood thatthe free leg 5 may be trapped also with the aid of a suitable grip inplace of the hook 17.

Finally, in a further version, a stirrup machine with a stirrup-legadjustment mechanism 25 according to the aforegoing description, mayinclude a suitable electronic computer for the maintenance,coordination, and control of all the functions of the process ofproduction of the three-dimensional stirrup 1 a. To this suitableelectronic computer are entered the necessary product characteristicsfor the production of the three-dimensional product 1 a. Thus, thecoordination and control of all the functions of the process ofproduction of the three-dimensional stirrup 1 a may preferably beeffected by a suitable electronic computer, in which are entered allnecessary data, such as product characteristics for the production ofthe product.

In the implementation of the invention the materials that are used aswell as the dimensions of the individual elements can be in accordancewith the requirements of the particular construction.

Various exemplary devices and methods have been illustrated in theaccompanying drawings and described in the foregoing detaileddescription but it will be understood that the claims to the methods anddevices shown and described are not limited to the particularembodiments described herein, as these may be capable of numerousrearrangements, modifications, and substitutions, and may be implementedin many forms and dimensions without departing from the scope and spiritof the claims set forth below. Consistent with legal precedent, thespirit and scope of the appended claims should not be limited to thedescription of the preferred versions contained herein. Accordingly, thetechniques and structures described and illustrated herein should beunderstood to be illustrative only and not limiting upon the scope ofthe present invention. The scope of the present invention is defined bythe appended claims, including known equivalents and unforeseeableequivalents at the time of filing of this application.

1. A machine for producing stirrups, comprising: a wire advancementmechanism; a first bending mechanism configured to receive wire fromsaid advancement mechanism and form planar stirrups therefrom; astirrup-leg adjustment mechanism configured to move at least one stirrupleg towards another; and, a second bending mechanism configured to benda third dimension into planar stirrups received by said stirrup-legadjustment mechanism.
 2. A machine for producing stirrups as claimed inclaim 1, further comprising: an arm in said stirrup-leg adjustmentmechanism.
 3. A machine for producing stirrups as claimed in claim 2,further comprising: a drive configured to controllably reciprocate saidarm.
 4. A machine for producing stirrups as claimed in claim 2, furthercomprising: trapping means functioning to trap a free stirrup leg, saidtrapping means located on said arm.
 5. The machine for producingstirrups as claimed in claim 2, wherein: said arm is located above theplane of receipt of stirrups.
 6. The machine for producing stirrups asclaimed in claim 2, wherein: said arm is located below the plane ofreceipt of stirrups.
 7. A machine for producing stirrups as claimed inclaim 1, further comprising: a first arm in said second bendingmechanism; and, a second arm configured to move cyclically around saidfirst arm.
 8. A machine for producing stirrups, comprising: a gripconfigured to restrain preformed, precut planar stirrups; a stirrup-legadjustment mechanism configured to move at least one stirrup leg towardsanother; and, a second bending mechanism configured to bend a thirddimension into planar stirrups received by said stirrup-leg adjustmentmechanism.
 9. A machine for producing stirrups as claimed in claim 8,further comprising: an arm in said stirrup-leg adjustment mechanism. 10.A machine for producing stirrups as claimed in claim 9, furthercomprising: a drive configured to controllably reciprocate said arm. 11.A machine for producing stirrups as claimed in claim 9, furthercomprising: trapping means functioning to trap a free stirrup leg, saidtrapping means located on said arm.
 12. The machine for producingstirrups as claimed in claim 9, wherein: said arm is located above theplane of receipt of stirrups.
 13. The machine for producing stirrups asclaimed in claim 9, wherein: said arm is located below the plane ofreceipt of stirrups.
 14. A machine for producing stirrups as claimed inclaim 8, further comprising: a first arm in said second bendingmechanism; and, a second arm configured to move cyclically around saidfirst arm.
 15. A process for producing stirrups, comprising: restraininga first leg of the stirrup, trapping a free leg of the stirrup with astirrup-leg adjustment mechanism; moving the free stirrup leg towardsthe first stirrup leg with said stirrup-leg adjustment mechanism; and,bending a third dimension in said planar stirrup when the free stirrupleg has been advanced towards the first stirrup leg a selected distanceby said stirrup-leg adjustment mechanism.
 16. A process for producingstirrups as claimed in claim 15, further comprising: controllablyreciprocating an arm of said stirrup-leg adjustment mechanism.
 17. Aprocess for producing stirrups as claimed in claim 16, furthercomprising: trapping the free stirrup leg to move it with reciprocationof said arm.
 18. A process for producing stirrups as claimed in claim15, further comprising: restraining the first leg of the stirrup with agrip.
 19. A process for producing stirrups as claimed in claim 15,further comprising: rotating a second arm around a first arm to bend thethird dimension.
 20. A process for producing stirrups as claimed inclaim 19, further comprising: forming the stirrup from wire with a firstbending mechanism.